Literal

A string literal is zero or more characters enclosed in double (") or single quotation marks ('). A string must be delimited by quotation marks of the same type (that is, either both single quotation marks, or both double quotation marks).

The following are examples of string literals:

"foo";
"bar";
"1234";
"one line \n new line";
"Joyo's cat";

An object literal is a list of zero or more pairs of property names and associated values of an object, enclosed in curly braces ({}).

The following is an example of an object literal. The first element of the car object defines a property, myCar, and assigns to it a new string, "Toyota"; the second element, the getCar property, is immediately assigned the result of invoking the function carTypes('Honda'); the third element, the special property, uses an existing variable (sales).

const sales = "BMW";

function carTypes(name) {
  return name === "Honda" ? name : `Sorry, we don't sell ${name}.`;
}

const car = {
  myCar: "Toyota",
  getCar: carTypes("Honda"),
  special: sales,
};

console.log(car.myCar); // Toyota
console.log(car.getCar); // Honda
console.log(car.special); // BMW

• Literal on Wikipedia